The term “disk drives” may refer to any of several types of devices, including but not limited to hard disk drives, floppy disk drives, and optical disk drives such as CD and DVD drives. These disk drives share a common characteristic of having one or more rotating recording media disks, and having a transducer positioned over a surface of the media. Disk drives also share the characteristic of being highly susceptible to damage, in part due to external shock and vibration and in another part due to internally generated vibrations that are not sufficiently damped by the disk drive mounting.
A drive using fixed rotating disks inside it is called a fixed disk drive. A drive using removable disks enclosed in an envelope is called a removable disk drive and the envelope containing the disks is called a removable disk cartridge. When the fixed disk drive itself is enclosed in an envelope and a shock resistant system is placed between them, then this assembly is called a removable drive module. A removable disk cartridge is removable from a disk drive while a removable drive module is removable from a docking device installed in a computer or an array chassis. Examples of removable disk cartridges include both industry standard 3.5″ floppy disk cartridges supplied by many manufacturers and removable hard disk cartridges supplied by companies such as Iomega, Castlewood and SyQuest. DataZone Corporation supplied a prior art removable drive module under the trademark DataBook. Olixir Technologies supplies a drive module under the trademark DataVault. A drive module can utilize an optical disk drive, a tape drive and other such drives besides hard, magnetic disk drives.
One application of the present invention relates to portable audio/video players technology using a Hard Disk Drive to store digital information. A music player is one such device. An “Ipod” made by Apple Computer and a “Zen” made by Creative Labs are examples of such music players. In known prior art, foam, polymeric material, viscous fluids, mechanical springs or a combination of these materials and devices provide shock and vibration protection to a disk drive. The following patents show state-of-the-art damping schemes. However, these fall short of achieving shock protection for a drop of more than 20 inches on a hard surface. The present invention overcomes this limitation.
Prior art includes United States Patent Application Publication 2005/0013107 A1 of Jan. 20, 2005 by Desai et al. This application presents a device utilizing a viscous fluid and describes earlier prior art relevant for shock protection of a hard disk drive in a removable module. The U.S. Pat. No. 6,351,374 to Sherry; U.S. Pat. No. 6,249,432 to Gamble et al.; U.S. Pat. No. 6,154,360 to Kaczeus Sr. et al.; U.S. Pat. No. 5,837,934 to Valavanis et al.; U.S. Pat. Nos. 4,638,383 and 4,568,988 to McGinlay et al., and U.S. Pat. No. 3,384,221 to Houtman provide limited teachings that refer only to foam materials, which do not achieve the desired degree of protection.
United States Patent Application 2005/0013107 A1 of Jan. 20, 2005 by Desai et al. is assigned to Olixir Technologies. It describes a mechanical energy dissipative element, MEDE, containing open cell foam, a viscous fluid and a compressible gas in a sealed flexible envelope. This device is capable of handling the drop requirement. However, the presence of a viscous fluid portends a possibility of leakage should the envelope gets punctured.
U.S. Pat. No. 6,154,360 to Kaczeus, Sr., et al. is assigned to DataZone Corporation. It shows a data storage subsystem that is capable of withstanding rough handling by partially surrounding a hard disk drive with a specially configured foam enclosure, formed, for example, of polyurethane foam.
U.S. Pat. No. 6,249,432 to Gamble et al. discloses a removable hard disk drive mounted in a carrier or tray for insertion into a docking bay. A three-component vibration damping system incorporating a polymeric material reduces vibration reaching the hard disk drive. This patent relates only to disk drives and not to general packaging and protecting of objects and systems.
U.S. Pat. No. 6,351,374 to Sherry discloses a hard disk drive module which uses insulator foam or other resilient material on one side or edge of the unit so as to maintain engagement with the other side or edge of a modular case. The resilient material can reduce shock to the disk drive unit due to impact on either the case or the chassis. Even a flexible cable leading to an electrical connector is attributed with the qualities of a shock absorber. This patent teaches a degree of shock absorption, but the extent of shock absorption appears to be low.
U.S. Pat. No. 5,837,934 to Valavanis et al. presents the use of foam sheets to provide shock absorption. It neither anticipates nor suggests applications for protecting other objects, systems, or devices by use of hook and loop device techniques.
U.S. Pat. Nos. 4,638,383 and 4,568,988 to McGinlay et al. provide a prior art disk drive design. These patents teach an anti-vibration mount using an elastic rubber material with very limited shock absorption capability.
U.S. Pat. No. 3,384,221 to Houtman claims the invention of adding a plurality of fingers or cuts in foam padding used for shock protection. A package can be dropped from a maximum height of 30 inches. Transmitted shock may be to reduced 11 Gs. However, this patent neither suggests nor discloses the use of any hook and loop device techniques for shock or vibration damping.
Additional prior art includes U.S. Pat. No. 6,347,411 to Darling; U.S. Pat. No. 6,339,532 to Boulay et al.; U.S. Pat. No. 6,039,299 to Ohnishi et al.; U.S. Pat. No. 5,995,365 to Broder et al.; U.S. Pat. No. 5,965,249 to Sutton et al.; and U.S. Pat. No. 5,510,954 to Wyler. These patents mention the use of viscous materials but not hook and loop device techniques.
U.S. Pat. No. 6,339,532 to Boulay et al. discloses mounting a disk drive by a layer of viscoelastic material, it does not anticipate the methods and apparatus used in the present invention.
U.S. Pat. No. 6,039,299 to Ohnishi, et al. discloses a viscous damper for a disk-reproducing unit, which is not subject to the shock danger encountered by a portable device.
U.S. Pat. No. 5,995,365 to Broder, et al. teaches the use of flexible cables to reduce the transfer of shock forces among electronic components such as a motherboard and a hard drive-carrier assembly. The Broder patent also teaches a method of using articulated arms as shock absorbers.
U.S. Pat. No. 5,965,249 to Sutton, et al. teaches a cold flowing material with high internal cohesion forces. It does not envision the methods and apparatus of the present invention.
U.S. Pat. No. 5,510,954 to Wyler teaches acoustic shielding. A key element is a fluid impervious barrier layer located next to sound absorptive porous foam. The acoustic shielding employs no hook and loop device techniques of the present invention.
Various other patents show background art. U.S. Pat. No. 5,546,250 to Diel uses an elastomer seal to cover the frame of a drive and absorb external loads applied to the edges of the housing. The protection system is applied to a disk drive perimeter rather than to a module. U.S. Pat. No. 4,891,734 to More et al. shows the use of an elastomer body to encapsulate an electronic assembly that is confined in a closed cavity of a structure subject to vibration and shock. U.S. Pat. No. 5,216,582 to Russell et al. describes a housing assembly that forms a fixed disk drive module for a low profile fixed disk drive that is shock-mounted therein. Both More and Russell use elastomer supports to protect from shock and vibration.
Some examples of the available technology in storage products are the music players by Apple Computer and Archos, and the XT 5000 external hard drive by Maxtor. These products use viscoelastic materials to absorb shock.
The above prior art analysis contrasts the essential or often occurring elements of certain embodiments of the present innovation. The present invention comprises additional embodiments that may or may not include all the elements listed above. All observations provided herein are directed to optional aspects of the present invention and are in no way expressions of limitations to the full scope of the present invention.
Portable Data Storage—A minimum requirement for portability of disk drives is the ability to survive multiple drops, from a height of more than two feet onto a hard surface, without damage to the drive. The present innovation helps meet this requirement
Removable media can meet the minimum shock requirement for portability. Iomega, SyQuest and Castlewood have shipped hard disk drive devices using removable media. The hard disk is contained in a cartridge that is removable from the drive. This makes for data portability. The inherent problem with removable media for hard disk drives is that the media becomes contaminated and this contamination transfers to the transducer in the drive. To counter the effects of the contamination, the recording capacity of the media is relatively decreased and the reliability of the overall system is compromised.
Floppy disk, CD, and DVD are other removable media. These media are much less susceptible to contamination. However, the capacity of the recording media is 0.01% to 1.0% of the capacity of a comparable size hard disk drive. These low capacities limit the application and usefulness of the removable media disk drives. In addition, the large numbers of floppy disks, CDs, and DVDs, which are often needed and used, require a large and carefully cataloged library. This same information is better stored on a single hard disk drive that has electronic means for cataloging.
Shipments of Disk Drives—There are design standards for common carrier shipments based upon size and weight of a container and whether the package is shipped on or off a pallet. Special shipping containers have to be designed to protect all shipments of disk drives. A percentage of common carrier shipments experience shocks in excess of the design standards, resulting in costly damage and possible loss of data. Individual disk drives are shipped in expensive and bulky boxes lined with foam or other bulky, shock absorbing, paper based material.
Environmental concerns and new laws require recycling of packing materials. Foam and other polymeric materials are extremely difficult to recycle. Secondary shipment costs of these packaging materials are high because they have to be used in large volumes for adequate protection of delicate peripherals or instruments.
There is a need for a disk drive cartridge that can withstand high G-shock for shipment by common carriers, eliminating the need for the design of special and expensive shipping containers.
Athletes and military personnel require helmets to protect them from head injuries. Presently, foam in a plastic or metal shell is used to construct a helmet. A better technology is needed to resist heavier shocks due to impacts received in the field.
Disk Drive Mounting—Whether the hard disk drive is mounted as a single component in a system or as an array of many disk drives, the mounting design is crucial to obtaining optimum performance and enhanced reliability. Previous mounting schemes use foams, polymeric materials, viscoelastic materials, mechanical springs or a combination of these materials and devices to provide the required shock and vibration damping to the disk drive.
These previous mounting schemes either mount the drive to a solid member of a case that incorporates shock and vibration damping material or mount the drive in a cartridge or some type of module having shock and vibration isolation and damping. The cartridge or module is then attached to a solid member of the case, with or without damping materials.
The design requirements for these mounting schemes are becoming more critical because:
1) Disk drive rotational speeds are increasing. Typical rotational speeds for hard disk drives have increased from 5400 rpm to 7200 rpm, with some drives now rotating at 10,000 rpm and 15,000 rpm. Slight imbalances will result in large vibrations and/or large forces that will accelerate component wear and induce damage to the drive(s).
2) Larger dense arrays of disk drives require smaller individual contributions in vibration forces from each individual drive. The drives are all rotating at the same speed. Thus, the probability of exciting natural vibration frequencies between the elements of the array is high.
Building of systems incorporating hard disk drives requires careful handling of each and every hard disk drive. Currently, during the process of removal from the shipping container and installation into a system or system module, there is no significant protection afforded to the hard disk drive. Typically, this operation is done by unskilled labor, worldwide. The largest numbers of hard disk drive failures happen during this installation process.
There is a need for a disk drive container that can both protect the hard disk drive during system assembly and meet the vibration and shock requirements. This is irrespective of whether the system uses a single hard disk drive or an array of disk drives.
To achieve the foregoing and other objects and in accordance with the purpose of the present invention, as embodied and broadly described herein, the method and apparatus of this invention may comprise the following.